# Development Of Generalized Well Semi-Analytical Coning Models

Project and Seminar Material for Petroleum Engineering

## Abstract

Oil deposits are often found in association with a communicating gas or water zone. The production of the oil often leads to the coning of water or gas. This dynamic interaction can be captured by a properly detailed reservoir simulation, which unfortunately may not always be practical. To bridge the gap, researchers over the years have developed both analytical and empirical methods of modelling gas and water coning in oil reservoir. The fundamental questions have always been: what is the critical rate of oil production; what is the breakthrough time if the critical rate is exceeded; and what is the post-breakthrough behaviour?

Using analytically derived line source vertical and horizontal well breakthrough time expressions, a method has been developed to estimate oil critical rate, breakthrough time and post-breakthrough trend for inclined wells. The Post-breakthrough prediction scheme was extended to vertical and horizontal wells. Simplified correlations have also been generated for the easy application of the method without the need of analyzing complex mathematical functions. Within the accuracy of the numerical simulation results, the breakthrough times for the inclined well were consistently and correctly predicted. Literature correlations and numerical simulation comparisons showed that the post-breakthrough production predictions tended to underpredict oil production, but the trends were much more consistent with simulation results than other correlations studied. To the best of the knowledge of the author, this is the first semi-analytical coning model of an inclined well, as well as, the first semi-analytical post-breakthrough trend prediction for vertical and horizontal wells.

## Chapter One

### Introduction And Problem Definition

#### 1.1 Introduction

Quite often, oil deposits are associated with an underlying water aquifer and an overriding gas cap. In many situations, the oil reserve is desired at the surface while the associated fluid is preferred within the reservoir either because they are not valuable at the surface as in the case of produced water or the resources to harness the gas if produced to the surface are not readily available. The reservoir water or gas may also be required for pressure maintenance in production optimization within the reservoir. Whatever may be the intention of prefering to keep the water and/or gas within the reservoir, it is found in practice a difficult goal to achieve due to coning of the unwanted fluid(s). Coning is the tendency of the underlying water in contact with the oil to rise locally towards the producing well due to the greater pressure depletion near the producing well and the viscous drag the production of oil is having on the water-oil interface. The same holds for the gas oil interface in which case the gas projects downwards towards the producing wellâ€™s perforation against gravitational force arising from gas-oil density difference. The projection is a result of viscous drag on the fluid interface and the local pressure depletion around the well due to oil production.

The production of either water or free gas with the oil will result in the reduction of the rate of oil production and the ultimate recovery of the oil. The reduction of oil production arises from the simple fact that some portion of the well bore that would be transporting oil will have to transport the unwanted fluid. Reduction in recovery arises from pressure depletion and trapping of oil behind the advancing unwanted fluid front. Ordinarily without coning, the unwanted fluid pushes the oil to the well as production progresses but with coning, the unwanted fluid leaves the oil behind, enters the well and may lead to early abandonment of the well.

The production of water has other damaging effect on hydrocarbon production profitability as it increases the spate and damage of corrosion. Corrosive agents like acid anhydride require the presence of water for ionization and chemical activity on metallic materials used in making the production string and other facilities. Obviously, the handling and disposal cost of produced water increases with the rate of coning. Depending on the prevailing environmental policy and the contaminant present in the produced water, this may constitute a huge cost burden. Gas handling, especially in areas with little market for gas, can become very demanding with gas coning. Treatment, pressurization and storage or re-injection may have dear financial implications. The environmentally-damaging alternative to the gas handling problem common in some countries is gas flaring. The latter constitutes enormous economic and environmental hazard.

As can be appreciated, for technical and economic reasons, it is crucial that coning be minimized or delayed. Thus coning minimization or delay is an important aspect of reservoir and production

management. Numerous studies1,2,3,4 have been conducted to understand the initiation and evolution of coning in order to control or minimize the stated negative consequences.

#### 1.2 Statement Of Problem

Work on coning had generally been pursued along the path of preventing or delaying cone generation and evolution, the time to breakthrough if advancement is not checked and the performance of the well after cone breakthrough. A number of empirical and analytical studies

have been conducted to model and determine these properties5. As will be discussed in detail, in the section on literature review, correlations and models for the determination of critical rate of oil production, time to breakthrough when producing at super-critical rate and the performance of the well after breakthrough have been developed for vertical and horizontal wells.

Development Of Generalized Well Semi-Analytical Coning Models

The complete material will be sent to you in just 2 steps.

Quick & Simple…

Make payment of â‚¦3,000: through USSD Transfer, Bank Mobile App, ATM Transfer, or POS Transfer to:

 Account No.: 0811003731 Name: Samphina Academy Account Type: Current

to pay with Debit Card

 FOR CLIENTS OUTSIDE NIGERIA: Click Here to pay with Debit Card (\$15) GHANA – Make Payment of 60 GHS to MTN MoMo, 0553978005, Douglas OsabuteyÂ Â  PAY WITH CRYPTOCURRENCY

Send the following details through Text Message or WhatsApp Messenger | +234-8143831497

• Payment DetailsÂ
• Development Of Generalized Well Semi-Analytical Coning Models

Â  Contact Our Help Desk

You may also like:

âš ď¸Ź Need a different topic? Perform a quick search

## Development Of Generalized Well Semi-Analytical Coning Models

### Disclaimer

This research material “Development Of Generalized Well Semi-Analytical Coning Models” is for research purposes and should be used as a guide in developing your research project / seminar work. For no reason should you copy word for word (verbatim) as samphina.com.ng will not be liable for any who copied the material.

The aim of providing this material is to reduce the stress of moving from one school library to another all in the name of searching for research materials. This service is legal because, all institutions permit their students to read previous projects, books, articles or papers while developing their own works. According to Austin Kleon “All creative work builds on what came before”.

samphina.com.ng is only providing this material “Development Of Generalized Well Semi-Analytical Coning Models” as a reference for your research. The paper should be used as a guide or framework for your own paper. The contents of this paper should be able to help you in generating new ideas and thoughts for your own research. Use it as a guidance purpose only.

## How to defend your research work

This is a general guide on how to defend your research work:

### 2. Strong Summary:

Summarizing your chapters will help keep your audience focused because it is easy for a mind to drift, so providing summaries will ensure your panel will follow along, even if they lose focus for a brief moment. Visual aides, such as graphs and power-point presentations can be very helpful. If you are going to use these, make sure you will practice your presentation with them.

### 3. Be Confident in Your Research Work:

Not knowing your topic “Development Of Generalized Well Semi-Analytical Coning Models” inside out will cause you to struggle and ultimately fail with your defense. You need to know the subject from every angle to ensure you are fully prepared for any question that may come your way.

### 4. Conclusion:

Reinforce your findings to conclude your defense. The finale of your presentation should focus on proving the work that has been done. You may need to recap on what has changed and remained unchanged, if is necessary.

### 5 . Listen:

Before you get defensive or recite a particular answer, make sure you truly understand the question being asked. Being a good listener is an important quality, because providing an inaccurate or off-topic answer will also weaken the validity of your paper.